Nivatakavachas

In Hindu mythology, the Nivatakavachas निवतकवच are a supernatural race of Asura demons, living deep under the oceans. Their name is Sanskrit for "of practical application - layer - garment" or similar.

They are extremely powerful in magic and mysticism and warfare, have powerful weapons, and perpetrate evil, but also are glorious and legendary beings. The Devas under Indra cannot overcome them despite repeated battles.

In the Ramayana, they strike an alliance with Ravana, after Ravana is unable to defeat them.

They are finally vanquished and destroyed entirely by Arjuna, the hero of the epic Mahabharata, who is asked to do so by his father Indra.

Some proponents of ancient astronaut theories (treating their name as nir-vata-kavacha निर्वतकवच, which can be translated with various meanings including "no-air-garment") theorized that this referred to aliens in spacesuits.

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